Optical semiconductor device and method of manufacturing optical semiconductor device

ABSTRACT

An optical semiconductor device includes a light emitting element having a first surface and a second surface, the first surface having a first electrode provided thereon, the second surface being located on the opposite side from the first surface and having a second electrode provided thereon; a first conductive member connected to the first surface; a second conductive member connected to the second surface; a first external electrode connected to the first conductive member; a second external electrode connected to the second conductive member; and an enclosure sealing the light emitting element, the first conductive member, and the second conductive member between the first external electrode and the second external electrode, and being configured to transmit light emitted from the light emitting element.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a division of and claims the benefit of priorityunder 35 U.S.C. §120 from U.S. Ser. No. 12/552,504 filed Sep. 2, 2009,and claims the benefit of priority under 35 U.S.C. §119 from JapanesePatent Application 2008-312149 filed Dec. 8, 2008, the entire contentsof each of which is incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an optical semiconductor device havinga light emitting element incorporated therein and a method ofmanufacturing the optical semiconductor device.

2. Description of the Related Art

An optical semiconductor device using a light emitting diode (LED) as alight emitting element is one of examples of conventional opticalsemiconductor devices. This light emitting diode employs a shape asshown in FIG. 19, for example. Specifically, an optical semiconductordevice 100 as a whole has a bullet shape, having a curved surfacethrough which light is emitted from a light emitting diode serving as alight emitting element. A first lead frame 101 has a basin-shapedconcave section 102 formed therein and a LED chip 103 is die-mounted ona bottom part of the concave section 102. Electrodes of the LED chip 103are electrically connected to the first lead frame 101 via a metal wire104 by wire bonding. Moreover, the LED chip 103 is also electricallyconnected to a second lead frame 105 via another metal wire 104.

The inside of the concave section 102 is sealed with a transparent resin106 that contains phosphor. Therefore, the LED chip 103 is also coveredwith the resin 106. Meanwhile, a side surface of the concave section 102functions as a reflection plate or a so-called reflector. When the LEDchip 103 emits light, the light is emitted in a direction of an arrowindicated in FIG. 19.

The first lead frame 101 having the LED chip 103 mounted on the concavesection 102, and the second lead frame 105 connected to the LED chip 103via the metal wire 104, are sealed by a sealing resin. The first leadframe 101 and the second lead frame 105 partially protrude from one endof an enclosure 107 in which all the foregoing components are sealed.Moreover, as described above, another end of the enclosure 107 is formedinto the curved surface and functions as a lens for outputting the lightemitted from the LED chip 103.

Another type of a conventional optical semiconductor device is a lightemitting diode package as disclosed in Japanese Patent ApplicationPublication No. 2006-310753, for example. This light emitting diodepackage has a LED element die-mounted on a package substrate and the LEDelement and the package substrate are connected through a bonding wireso as to be connected electrically to each other.

BRIEF SUMMARY OF THE INVENTION

However, the above-described light emitting diode package having theconfiguration as disclosed in Japanese Patent Application PublicationNo. 2006-310753 and the optical semiconductor device of the bullet shapeas shown in FIG. 19 have the following problems.

Specifically, a manufacturing process of each of these devices roughlyincludes a step of manufacturing the LED chip (the light emittingelement) and a step of packaging the manufactured LED chip (the lightemitting element). With the necessity to include these two steps havingno relation with each other at all, however, the manufacturing of suchan optical semiconductor device tends to have a larger number ofprocessing steps. This results in an increase in the manufacturing costsand reduction in productivity.

Meanwhile, some light emitting diode packages employ a resin made of amixture of phosphor and a ceramic or epoxy resin, for example, as areflection plate (a reflector) for reflecting light emitted from a lightemitting element. Nevertheless, employing such a reflector may cause anincrease in the number of components constituting an opticalsemiconductor device and deterioration of the reflector due to the lightemitted from the light emitting element.

The present invention has been made to address the above-describedproblems. An object of the present invention is to provide an opticalsemiconductor device and a method of manufacturing an opticalsemiconductor device, which are capable of reducing the number ofcomponents and the number of manufacturing steps to reduce manufacturingcosts and of improving productivity as well.

A first aspect of an embodiment of the present invention provides anoptical semiconductor device which includes a light emitting elementhaving a first surface and a second surface, the first surface having afirst electrode provided thereon, the second surface being located onthe opposite side from the first surface and having a second electrodeprovided thereon; a first conductive member connected to the firstsurface of the light emitting element; a second conductive memberconnected to the second surface of the light emitting element; a firstexternal electrode connected to the first conductive member; a secondexternal electrode connected to the second conductive member; and anenclosure sealing the light emitting element, the first conductivemember, and the second conductive member between the first externalelectrode and the second external electrode, and being configured totransmit light emitted from the light emitting element.

A second aspect of an embodiment of the present invention provides amethod of manufacturing an optical semiconductor device which includesthe steps of dividing a light emitting element wafer on a support bodyinto light emitting elements by cutting the light emitting element waferin a direction toward the support body; rearranging the light emittingelements by expanding the support body; forming a first conductivemember on a first electrode provided on a first surface of each of thelight emitting elements; sealing the light emitting elements and thefirst conductive members by an enclosure; detaching the support body andforming a second conductive member on a second electrode provided on asecond surface of each of the light emitting elements; sealing thesecond electrodes and the second conductive members by the enclosure;connecting a first external electrode to the first conductive member andconnecting a second external electrode to the second conductive member;performing dicing between each adjacent two of the light emittingelements to divide optical semiconductor devices from each other; andforming plating films respectively on the first external electrode andthe second external electrode by plating.

A third aspect according to an embodiment of the present inventionprovides a method of manufacturing an optical semiconductor device whichincludes the steps of dividing a light emitting element wafer on asupport body into light emitting elements by cutting the light emittingelement wafer in a direction toward the support body; rearranging thelight emitting elements by expanding the support body; forming a firstconductive member on a first electrode provided on a first surface ofeach of the light emitting elements; sealing the light emitting elementsand the first conductive members by an enclosure; detaching the supportbody and forming a second conductive member on a second electrodeprovided on a second surface of each of the light emitting elements;sealing the second electrodes and the second conductive members by theenclosure; grinding the first conductive member and the enclosuresealing the first conductive member so that the first conductive memberand the enclosure are oblique with respect to the first surface; formingon the ground surface a first external electrode to be connected to thefirst conductive member; grinding the second conductive member and theenclosure sealing the second conductive member so that the secondconductive member and the enclosure are oblique with respect to thesecond surface; forming on the ground surface a second externalelectrode to be connected to the second conductive member; performingdicing between each adjacent two of the light emitting elements todivide optical semiconductor devices from each other; and formingplating films respectively on the first external electrode and thesecond external electrode by plating.

BRIEF DESCRIPTION OF THE SEVERAL DRAWINGS

FIG. 1 is a perspective view showing an entire optical semiconductordevice according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view of the optical semiconductor deviceshown in FIG. 1 which is taken along the line A-A.

FIG. 3 is a first process drawing for explaining a method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 4 is a second process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 5 is a third process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 6 is a fourth process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 7 is a fifth process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 8 is a sixth process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 9 is a seventh process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 10 is an eighth process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 11 is a ninth process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 12 is a tenth process drawing for explaining the method ofmanufacturing the semiconductor device according to the first embodimentof the present invention.

FIG. 13 is a perspective view showing an entire optical semiconductordevice according to a second embodiment of the present invention.

FIG. 14 is a cross-sectional view of the optical semiconductor deviceshown in FIG. 13 which is taken along the line B-B.

FIG. 15 is a first process drawing for explaining a method ofmanufacturing the semiconductor device according to the secondembodiment of the present invention.

FIG. 16 is a second process drawing for explaining the method ofmanufacturing the semiconductor device according to the secondembodiment of the present invention.

FIG. 17 is a third process drawing for explaining the method ofmanufacturing the semiconductor device according to the secondembodiment of the present invention.

FIG. 18 is a fourth process drawing for explaining the method ofmanufacturing the semiconductor device according to the secondembodiment of the present invention.

FIG. 19 is a cross-sectional view for explaining a conventional opticalsemiconductor device.

DETAILED DESCRIPTION OF THE INVENTION

Now, embodiments of the present invention will be described below indetail with reference to the accompanying drawings.

First Embodiment

An entire optical semiconductor device 1 according to a first embodimentof the present invention has a substantially rectangular solid shape asshown in FIG. 1. The optical semiconductor device 1 is provided with apair of external electrodes 2, 2. The optical semiconductor device 1 isalso provided with a region sealed by an enclosure 3, the regioninterposed between the pair of external electrodes 2, 2. This enclosure3 seals a light emitting element (not shown in FIG. 1) which is providedinside the optical semiconductor device 1. Each of the paired externalelectrodes 2, 2 is plated. Five surfaces of each external electrode 2except a surface contacting the enclosure 3 are covered with a platingfilm 4 to constitute five-surface electrodes.

The optical semiconductor device 1 is placed on a wiring pad provided ona substrate, which is not shown from a view angle illustrated in FIG. 1,for example, in a way that the external electrodes 2, 2 come intocontact with the wiring pads. Then, an adhesive such as solder isdisposed to cover the wiring pad and the external electrodes 2, 2 sothat the substrate and the optical semiconductor device 1 areelectrically connected to each other.

FIG. 2 is a cross-sectional view of the optical semiconductor device 1shown in FIG. 1 which is taken along the line A-A. A light emittingelement 5 is located substantially in the center in a longitudinaldirection of the optical semiconductor device 1 and is sandwiched by thepair of external electrodes 2, 2 with the conductive members 6interposed in between respectively. Moreover, the enclosure 3 is alsosandwiched by the pair of external electrodes 2, 2 and seals therein thelight emitting element 5 and conductive members 6. The plating film 4 isformed on the five surfaces of each external electrode 2.

The light emitting element 5 has a substantially rectangular solid shapeand favorably a LED (light emitting diode) chip is employed therefore.The element is in a cube measuring about 200 μm to 300 μm per side, forexample. A first electrode 5 a 1 of the light emitting element 5 isprovided on a first surface 5 a of the light emitting element 5. Asecond electrode 5 b 1 of the light emitting element 5 is provided on asecond surface 5 b on the opposite side from the first surface 5 a.Although the light emitting element 5 includes a p-type electrode and ann-type electrode, the first electrode 5 a 1 and the second electrode 5 b1 may be the p-type and the n-type, respectively, or vice versa.

A first conductive member 6 a is connected to the first surface 5 a ofthe light emitting element 5 and a second conductive member 6 b isconnected to the second surface 5 b thereof. Moreover, the firstexternal electrode 2 a is connected to the first conductive member 6 aand the second external electrode 2 b is connected to the secondconductive member 6 b so as to sandwich the first conductive member 6 aand the second conductive member 6 b. By providing the light emittingelement 5 inside the optical semiconductor device 1 as described aboveand applying a voltage from each external electrode 2 to the firstelectrode 5 a 1 or the second electrode 5 b 1 through the correspondingone of the conductive members 6, a current flows between the firstelectrode 5 a 1 and the second electrode 5 b 1 and the light emittingelement 5 emits light.

Meanwhile, surfaces areas of the first surface 5 a and the secondsurface 5 b each provided with the electrode of the light emittingelement 5 and surface areas of the first conductive member 6 a and thesecond conductive member 6 b are formed smaller than surface areas ofthe first external electrode 2 a and the second external electrode 2 bto be connected via the conductive members 6. The light emitting element5 and the conductive members 6 designed to have such dimensions asdescribed above can be located in the center inside the opticalsemiconductor device 1 and can be surrounded and sealed by the enclosure3.

It is ideal that the light emitting element 5 is surrounded by nothingwhen the light emitting element 5 emits light. However, since thevoltage is applied to the light emitting element 5 through theconductive members 6, the light emitting element 5 needs to be connectedto the conductive members 6 to emit light. Each of the conductivemembers 6 only needs to be large enough to apply voltage required tocause the light emitting element 5 to emit light. The size (thickness)of the conductive members 6 is determined in consideration of allfactors including the voltage required by the light emitting element 5,the material of the conductive members 6, and the like.

Next, a method of manufacturing the optical semiconductor device 1according to the first embodiment of the present invention will bedescribed with reference to FIG. 3 to FIG. 12.

First, FIG. 3 shows a LED wafer (a light emitting element wafer) W.Though not illustrated in FIG. 3, the p-type electrode or the n-typeelectrode (the first electrode 5 a 1 or the second electrode 5 b 1) isformed on both surfaces of the wafer W. Meanwhile, in the embodiment ofthe present invention, the LED wafer W provided with the electrodesformed on both surfaces thereof is employed. However, the wafer W may beformed of, for example, a LED formed by depositing crystals by using asapphire substrate or a LED formed by use of SiC (silicon carbide).

The wafer W is placed on a support body S and is divided into pieces(see FIG. 4). To divide the wafer W into pieces, the wafer W is diced,for example, from one surface to the other surface of the wafer W placedon the support body S. The method of dividing the wafer W into pieces isnot limited only to this method and a method of forming a crack in acutting position with a laser to divide the wafer into pieces may beemployed, for example. After dividing the wafer W into pieces, multiplelight emitting elements 5 thus divided into pieces are formed on thesupport body S as shown in FIG. 4.

Next, the light emitting elements 5 on the support body S are rearrangedfrom the original positions at the time of dividing into pieces in orderto manufacture the optical semiconductor device 1. This rearrangement isperformed by expanding (stretching) the support body S in a directionalong arrows to spread distances between the adjacent light emittingelements 5 as shown in FIG. 5, for example. Here, as the material of thesupport body S to be expanded, favorably used is polyvinyl chloride,olefin resin or PET, for example.

The light emitting elements 5 are rearranged here by stretching thesupport body S which is also used at the time of dividing the wafer Winto pieces as shown in FIG. 4. However, when a dicing sheet is used fordividing the wafer W into pieces, for example, the rearrangement may beperformed by placing one surface of each divided light emitting element5 onto another sheet suitable for rearrangement, such as theabove-described support body S.

Further, the LED wafer generally is smaller in size than a semiconductorchip wafer. Therefore, the number of the light emitting elements 5 to beobtained by dividing the LED wafer into pieces is often fewer than thenumber of semiconductor chips to be obtained. Accordingly, whenrearranging the divided light emitting elements 5, it is also possibleto place the light emitting elements 5 obtained from multiple LED wafersonto a single support body. This placement makes it possible tomanufacture the optical semiconductor devices 1 collectively and therebyto improve productivity thereof.

Then, the conductive members 6 are connected to the electrodes of eachof the rearranged light emitting elements 5. First, a description willbe given of a method of connecting the first conductive member 6 a ontothe first electrode 5 a 1 provided on the first surface 5 a of the lightemitting element 5. Here, the surface of the light emitting element 5contacting the support body S represents the second surface 5 b in FIGS.6 to 9.

As shown in FIG. 6, a mask M is provided except regions on which thefirst conductive members 6 a are formed in order to connect the firstconductive members 6 a to the first electrodes 5 a 1. The mask M is alsoprovided on the first surfaces 5 a and spaces between the each adjacenttwo light emitting elements 5 except the regions on the first electrodes5 a 1 on which the conductive members 6 a are formed. In this state, thefirst conductive members 6 a are formed by use of an electrolyticplating method, for example (see FIG. 7). Copper (Cu) is favorably usedfor the conductive member 6, for example.

FIG. 8 shows a state where the mask M is removed and the firstconductive members 6 a are connected to the first electrodes 5 a 1. Asdescribed previously, in order not to prevent the light emitting element5, when emitting light, from emitting light, each of the firstconductive members 6 a is designed to have a small area so as to occupyonly a small area of the first surface 5 a of the light emitting element5.

In this state, the light emitting elements 5 and the first conductivemembers 6 a are sealed by using the enclosure 3 as shown in FIG. 9. Theenclosure 3 is made of resin that includes phosphor therein. For thisreason, when the light emitting elements 5 sealed by the enclosure 3emit light, the light emitted from the light emitting element 5 not onlydirectly passes through the enclosure 3 and is emitted outward from theoptical semiconductor device 1 but also is absorbed by the phosphor. Asa consequence, the phosphor also emits light which is then emittedoutward from the optical semiconductor device 1.

After the light emitting elements 5 and the first conductive members 6 aare sealed by the enclosure 3, the enclosure 3 is subjected to grindingso that the surface of each first conductive member 6 a to come intocontact with each external electrode 2 a aligns with the surface of theenclosure 3. FIG. 9 shows the state in which the grinding process isfinished and the surface of each first conductive members 6 a to comeinto contact with each external electrodes 2 a aligns with the surfaceof the enclosure 3. Thereafter, the support body S is detached toproceed to a step of connecting the second conductive members 6 b to thesecond electrodes 5 b 1 of the light emitting elements 5.

Note that the step of connecting the second conductive members 6 b tothe second electrodes 5 b 1 of the light emitting elements 5 isperformed in the same way as the step of connecting the first conductivemembers 6 a to the first electrodes 5 a 1 which is described withreference to FIGS. 6 to 9. Accordingly, description of this step will beomitted herein.

FIG. 10 shows a state in which the first conductive members 6 a and thesecond conductive members 6 b are respectively connected to the firstelectrodes 5 a 1 and the second electrodes 5 b 1 of the light emittingdevices 5 and these constituents are sealed by the enclosure 3.

Here, the external electrodes 2 a are connected to the first conductivemembers 6 a which are ground so as to be aligned with the enclosure 3.FIG. 11 is a view showing this state. The external electrodes 2 a areformed by an electroless plating method by using the mask M as shown inFIG. 6, for example. Copper (Cu) is favorably used for the externalelectrodes 2 a, for example.

Here, the surfaces of the external electrodes 2 to be connected to theconductive members 6 also function as reflectors for reflecting lightemitted from the light emitting elements 5. Meanwhile, the externalelectrodes 2 are made of metal and therefore have excellent durabilitywithout being deteriorated by light emitted from the light emittingelements 5.

After the external electrodes 2 b are also connected to the secondconductive members 6 b, the resultant body is diced, between eachadjacent two of the light emitting elements 5, 5 with a blade which isthinner than an interval of each adjacent two of the light emittingelements 5, 5 as shown with broken lines of FIG. 12. In this way, theindividual optical semiconductor devices 1 are formed as shown in FIG.1.

Thereafter, if, for example, the optical semiconductor device 1 issubjected to barrel plating or immersed into a plating tank, it ispossible to form the plating films 4 on five surfaces of each of thefirst external electrode 2 a and the second external electrode 2 b. Forforming the plating film, for example, Nickel-tin (Ni—Sn) plating ornickel-gold (Ni—Au) plating is favorably used. This plating process maybe the formation of a single layer on the surfaces of the first externalelectrode 2 a and the second external electrode 2 b or the lamination ofmultiple layers thereon by means of silver plating, solder plating, andthe like. Use of the solder plating on the outermost layer in particularmakes it possible to improve wettability with solder to be used forconnecting the optical semiconductor device 1 to a substrate.

As described above, an employment of the configuration to seal thesurrounding of the light emitting element 5 with the enclosure 3 and toelectrically connect the electrode surfaces provided on the lightemitting element 5 to the pair of external electrodes 2 via theconductive members 6 makes it possible to reduce the number ofcomponents and the number of manufacturing steps. Hence it is possibleto provide the optical semiconductor device and the method ofmanufacturing the optical semiconductor device, which are capable ofreducing the manufacturing costs and improving productivity.

Moreover, the surface (a first connection surface 2 a 1) of the firstexternal electrode 2 a to be connected to the first conductive member 6a or the surface (a second connection surface 2 b 1) of the secondexternal electrode 2 b to be connected to the second conductive member 6b is formed in parallel with the first surface 5 a or the second surface5 b of the light emitting element 5 as shown in FIG. 2. Therefore, lightis directed to all directions through the enclosure 3 sealing thesurrounding thereof. As a consequence, directivity of the light emittingelement 5 is weakened so that the light emitted from the light emittingelement 5 is not limited to be directed to any particular direction.

Further, as being used to seal the light emitting element 5, theenclosure 3 which has flexibility makes it possible to prevent the lightemitting element 5 from being damaged at the time of manufacturing theoptical semiconductor device 1.

Here, it is needless to say that an employment of five-surfaceelectrodes in the semiconductor device according to the embodiment ofthe present invention has following advantageous effects in addition tothe above-mentioned effects at the time of mounting the semiconductordevice on the substrate. Specifically, a state of solder bonding can bevisually checked at the time of the mounting, and the soldering betweenthe external electrode and the substrate can form a sufficient filletthat reduces damages attributable to external forces such as impacts,for example.

Second Embodiment

Next, a second embodiment of the present invention will be described. Inthe second embodiment, the same constituents as the constituentsdescribed above in the first embodiment will be designated by the samereference numerals and duplicate explanation of the same constituentswill be omitted herein.

An optical semiconductor device 11 of the second embodiment is differentfrom the optical semiconductor device 1 of the first embodiment in ashape of the external electrodes. As described previously, in theoptical semiconductor device 1 according to the first embodiment, thesurfaces (the first connection surface 2 a 1 and the second connectionsurface 2 b 1) of each of the paired external electrodes 2 to beconnected to the corresponding conductive member 6 are respectivelyformed in parallel to the surfaces of the light emitting element 5. Onthe other hand, in the optical semiconductor device 11 according to thesecond embodiment, surfaces (a first connection surface 12 a 1 and asecond connection surface 12 b 1) of paired external electrodes 12 to beconnected to corresponding conductive members 16 are respectively formedobliquely to the surfaces of the light emitting element 5.

FIG. 13 is a perspective view showing the entire optical semiconductordevice 11 according to the second embodiment of the present invention.FIG. 14 is a cross-sectional view showing a cross section of the opticalsemiconductor device 11 shown in FIG. 13 which is taken along the lineB-B.

As simply illustrated in FIG. 13 or in the cross-sectional view of FIG.14, a surface (the first connection surface 12 a 1) of a first externalelectrode 12 a connected to a first conductive member 16 a is formedobliquely and obliquely faces the first surface 5 a of the lightemitting element 5. In addition, a surface (the second connectionsurface 12 b 1) of a second external electrode 12 b connected to asecond conductive member 16 b is also formed obliquely and obliquelyfaces the second surface 5 b of the light emitting element 5.

Meanwhile, surfaces of the conductive members 16 to be respectivelyconnected to the external electrodes 12 are formed so as to fit to theshapes (inclinations) of the first connection surface 12 a 1 and thesecond connection surface 12 b 1 of the external electrodes 12.Moreover, the shape of an enclosure 13 for sealing the light emittingelement 5 and the conductive members 16 is also formed into asubstantially trapezoidal shape so as to fit to the shapes(inclinations) of the first connection surface 12 a 1 and the secondconnection surface 12 b 1 of the external electrodes 12 whenillustrating the optical semiconductor device 11 from a direction asshown in FIG. 14, for example.

As the first external electrode 12 a and the second external electrode12 b are formed into the above-described shapes, the light emitted fromthe light emitting element 5 is reflected by the first connectionsurface 12 a 1 and the second connection surface 12 b 1 and is directedto a direction of an arrow shown in FIG. 14. Here, it is needless to saythat the shapes (inclinations) of the first connection surface 12 a 1and the second connection surface 12 b 1 can be designed as appropriate.Moreover, the first connection surface 12 a 1 and the second connectionsurface 12 b 1 may be formed so as to face each other symmetrically withrespect to the light emitting element 5. Alternatively, the shapes(inclinations) of these surfaces may be formed differently from eachother.

The optical semiconductor device 11 is manufactured in accordance withthe following steps. Here, the steps in the method of manufacturing theoptical semiconductor device 1 which have been described with referenceto FIGS. 3 to 10 in the first embodiment are also applied to the methodof manufacturing the optical semiconductor device 11. Accordingly, theduplication explanation will be omitted in the following description.

As shown in FIG. 10, the light emitting element 5, the first conductivemember 16 a, and the second conductive member 16 b are sealed by theenclosure 13. Thereafter, as shown in FIG. 15, regions of the firstconductive members 16 a and the enclosure 13 to be connected to thefirst external electrodes 12 a are ground. This grinding process may bedone by using a laser or a grinder, for example. Surfaces (regions) thatappear after the grinding process constitute the connection surfaces(the first connection surfaces 12 a 1) between the first conductivemembers 16 a and the first external electrodes 12 a when the firstexternal electrodes 12 a are formed. Moreover, an angle a shown in FIG.15 serves as an angle of the reflectors when the external electrodes 12a are formed.

After the grinding process, the mask M is disposed in a predeterminedposition to form the first external electrodes 12 a. The first externalelectrodes 12 a are formed in accordance with the electroless platingmethod, for example, as similar to the method of forming the externalelectrodes 2 of the optical semiconductor devices 1 in theabove-described first embodiment. Copper (Cu) is favorably used for thefirst external electrodes 12 a, for example. FIG. 16 shows a state afterthe first external electrodes 12 a are formed.

Thereafter, as shown in FIG. 17, the mask M used for forming the firstelectrodes 12 a is removed and then the second external electrodes 12 bto be connected to the second conductive members 16 b are formed. Themethod of forming the second external electrodes 12 b is the same as themethod of forming the first external electrodes 12 a.

After the external electrodes 12 b are connected to the secondconductive members 16 b, the resultant body is diced, between eachadjacent two of the light emitting elements 5, 5, with the blade whichis thinner than an interval of each adjacent two of the light emittingelements 5, 5 as shown with broken lines of FIG. 18. In this way, theindividual optical semiconductor devices 11 are formed as shown in FIG.13.

Thereafter, if, for example, the optical semiconductor device 11 issubjected to barrel plating or immersed into a plating tank, the platingfilms 4 are formed on five surfaces of each of the first externalelectrode 12 a and the second external electrode 12 b.

As described above, an employment of the configuration to seal thesurrounding of the light emitting element 5 with the enclosure 13 and toelectrically connect the electrode surfaces provided on the lightemitting element 5 to the pair of external electrodes 12 via theconductive members 16 makes it possible to reduce the number ofcomponents and the number of manufacturing steps. Hence it is possibleto provide the optical semiconductor device and the method ofmanufacturing the optical semiconductor device, which are capable ofreducing the manufacturing costs and improving productivity.

In particular, by forming each of the external electrodes 12 into theabove-described shape, it is possible to direct the light emitted fromthe light emitting element 5 to a predetermined direction and thereby tosupply the optical semiconductor device having finer directivity.

Further, as being used to seal the light emitting element 5, theenclosure 13 which has flexibility makes it possible to prevent thelight emitting element 5 from being damaged at the time of manufacturingthe optical semiconductor device 1.

Here, it is needless to say that an employment of five-surfaceelectrodes in the semiconductor device according to the embodiment ofthe present invention has following advantageous effects in addition tothe above-mentioned effects at the time of mounting the semiconductordevice on the substrate. Specifically, a state of solder bonding can bevisually checked at the time of the mounting, and the soldering betweenthe external electrode and the substrate can form a sufficient filletthat reduces damages attributable to external forces such as impacts,for example.

It is to be understood that the present invention is not limited only tothe above-described embodiments and that the present invention may berealized in a practical phase by modifying the constituents withoutdeparting from the scope of the invention. Moreover, various otherembodiments of the invention may be achieved by appropriately combiningthe constituents disclosed in the above-described embodiments. Forexample, it is possible to eliminate some constituents out of all theconstituents described in any of the embodiments. Alternatively, it ispossible to appropriately combine the constituents that appear indifferent embodiments.

This invention is not limited to the above-described embodiment. Thepresent invention can also be implemented by modifying the constituentswithout departing from the scope of the invention. Moreover, otheraspects of the present invention can be achieved by appropriatelycombining the constituents that are disclosed in the above-describedembodiment. For example, several constituents can be eliminated from allthe constituents of the embodiment. Further, it is also possible tocombine the constituents that are disclosed in different embodiments asappropriate.

1. A method of manufacturing an optical semiconductor device comprisingthe steps of: dividing a light emitting element wafer on a support bodyinto light emitting elements by cutting the light emitting element waferin a direction toward the support body; rearranging the light emittingelements by expanding the support body; forming a first conductivemember on a first electrode provided on a first surface of each of thelight emitting elements; sealing the light emitting elements and thefirst conductive members by an enclosure; detaching the support body andforming a second conductive member on a second electrode provided on asecond surface of each of the light emitting elements; sealing thesecond electrodes and the second conductive members by the enclosure;connecting a first external electrode to the first conductive member andconnecting a second external electrode to the second conductive member;performing dicing between each adjacent two of the light emittingelements to divide optical semiconductor devices from each other; andforming plating films respectively on the first external electrode andthe second external electrode by plating.
 2. A method of manufacturingan optical semiconductor device comprising the steps of: dividing alight emitting element wafer on a support body into light emittingelements by cutting the light emitting element wafer in a directiontoward the support body; rearranging the light emitting elements byexpanding the support body; forming a first conductive member on a firstelectrode provided on a first surface of each of the light emittingelements; sealing the light emitting elements and the first conductivemembers by an enclosure; detaching the support body and forming a secondconductive member on a second electrode provided on a second surface ofeach of the light emitting elements; sealing the second electrodes andthe second conductive members by the enclosure; grinding the firstconductive member and the enclosure sealing the first conductive memberso that the first conductive member and the enclosure are oblique withrespect to the first surface; forming on the ground surface a firstexternal electrode to be connected to the first conductive member;grinding the second conductive member and the enclosure sealing thesecond conductive member so that the second conductive member and theenclosure are oblique with respect to the second surface; forming on theground surface a second external electrode to be connected to the secondconductive member; performing dicing between each adjacent two of thelight emitting elements to divide optical semiconductor devices fromeach other; and forming plating films respectively on the first externalelectrode and the second external electrode by plating.